The following background information may present examples of specific aspects of the prior art (e.g., without limitation, approaches, facts, or common wisdom) that, while expected to be helpful to further educate the reader as to additional aspects of the prior art, is not to be construed as limiting the present invention, or any embodiments thereof, to anything stated or implied therein or inferred thereupon.
Typically, manhole covers frequently weigh five hundred pounds and upward. Because of their weight and unwieldy size, difficulties are encountered in lifting and removing the manhole covers. Likewise, the fit between the cover and the manhole may be tight, jammed or wedged, making it difficult to loosen or move. Often, a person lifting a manhole cover with conventional equipment such as crowbars, hooks and the like, must stand close to the manhole cover. Consequently there is a considerable risk of falling into the manhole.
Also, the sheer weight of a manhole cover may over-strain a man, or a sudden jerk or pull may cause internal damage and injury. It has long been recognized by safety engineers that such lifting and removing and replacing of manhole covers, constitutes an industrial hazard. The present invention helps solve the problems associated with manual lifting of manhole covers to lower fatigue and back injury.
Typically, machines consist of a number of elements, such as gears and ball bearings that work together in a complex way. Nonetheless, no matter how complex they are, all machines are based in some way on six types of simple machines. These six types of machines are the lever, the wheel and axle, the pulley, the inclined plane, the wedge, and the screw.
It is known that in machines that transmit mechanical energy, the ratio of the force exerted by the machine to the force applied to the machine is known as mechanical advantage. Under mechanical advantage the distance the load will be moved will be only be a fraction of the distance through which the effort is applied. Simple machines can be adjusted, moved, and manipulated to increase the mechanical advantages necessary to move manhole cover
Other proposals have involved leveraging mechanical energy to displace a manhole cover. The problem with these moving devices is that they are not portable. Also, they do not lift, lower, rotate, extend, retract, and laterally displace a manhole cover over a short distance and in difficult to access areas. Even though the above cited moving devices meet some of the needs of the market, a portable manhole cover moving assembly and method for moving a manhole cover to lift, lower, rotate, extend, retract, and laterally displace a manhole cover over a short distance and in difficult to access areas is still desired.